Stumbled across this language Lua while googling the Roblox game my son is addicted to..
Says it's also what Angry Birds is programmed in...
What's nice about it to me is that it has a C-ish looking syntax but also something like Spin and that the bytecode interpreter comes in at 100 kB on a PC. If it is also 100 kB on P2, this sounds really nice.
If P2 does get that full 512kB, using a100 kB for the interpreter doesn't sound too bad. I think P1 used 16 kB out of 64 kB (RAM+ROM) for the interpreter.